Art of rating cyclic motions



Sept. 12, 1944. w. KOHLHAGEN ART OF RATING CYCLIC MOTIONS Filed April 15, 1942 3 Sheets-Sheet l Sept. 12, 1944. w. KOH LHAGEN 2,353,073

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Patented Sept. 12,

ART. OF RATING GYCIJC MOTIONS Walter Kohlhagen, Elgin, lll., assignor to Elgin National Watch Company, Elgin, 111., a corporation of Illinois Application April 15,1942, Serial No. 439,128

23 Claims.

This invention relates to the rating of cyclic motions, and is concerned with methods and apparatus by which such determinations may be conveniently and accurately made.

A feature of the invention is the determination of the rate of oscillating movements of devices which have a plurality ofparts so that a cycle of movement produces a succession of impulses, and includes selection among such impulses so that a like point of eachcycle is used for comparison.

Another feature is the coordination of starting and rating instrumentalities so that the rating system is released concurrently with the selection of a starting point for the oscillating movement itself.

A further feature is the employment of loading and firing means responsive to individual phenomena of cyclic groups, together with means for selectively employing the same for starting the rating at a predetermined point of a cycle and thereafter effecting a comparison of the time spacing between like points in successive cycles.

A particular feature of the invention, when employed for determining the rate of cyclically oscillating structures such as watch movements, is the inclusion of means for storing energy in the structure whereby it may enter its oscillation, together with a control of the initiation of testing concurrently with the release of the structure for performance of its oscillating movements.

With these and other features as objects in view, as will appear from the following description and the drawings, an illustrative form of practicing the invention is set forth in the drawings, in which:

Figure 1 is a general view of the embodiment of the invention with a perspective showing of certain mechanical structures.

Figure la is a conventionalized circuit diagram of electrical parts employed with the mechanical structures of Figure 1.

Figure 2 is a longitudinal axial view through the mechanical supporting structure utilized with a watch balance.

Figure 3 is a sectional view showing a control and air driving means for maintaining the oscillation of the balance.

Figure 4 is a diagrammatic view indicating the relation of the light beam to spokes of a balance wheel while quiescent at the neutral axis.

Figures 5, 6 and 'l are graphs illustrating the balance movement and the relative time positions of current impulses.

The invention is illustratively shown as em-- ployed in determining the rate of a standard type of balance assembly which has two spokes and which oscillates through a total angle of greater than 360 degrees in actual employment.

In Figure l, a general frame is conventionally shown as a supporting member I!) having struc-" tures for supporting the several mechanical parts in proper relationship to one another, and for permitting their required relative movements. A bearing ll supports a hollow flange l2 of a disk l3 which has an eccentrically extending pin M provided at its end with pincers I! for engaging the end of the hair spring HS ofa balance illustrated as having the usual pin P, the balance wheel BW, and the staff S. One end of this staff (at the left in Figs, 1 and 2) is rotatably received in an appropriate cavity in the end of a supporting member it which extends coaxially through the disk i3 and is provided with a collar 11 which limits its movement toward the right in Figure 2 under the urgency of a spring It. The supporting member I6 is provided at its end with a knob ill by which the operator may retract the same for engaging or releasing abalance.

The other end of the balance is similarly received in a cavity at the end of the supporting member 23 which is rotatably mounted in a bearing 24 and is provided at its opposite end with a pinion 25. AdJacent the balance, the supporting member 23 carries a disk 26 which is secured to turn with the member 23 and is provided with a slidable plunger 21 which is mounted eccentrically to the common axis of the supporting members It, 23 at a proper distance for entering one of the spaces in the balance wheel BW (Fig. 3), so that it can engage with one of the spokes thereof. The plunger 21 is retracted (toward the right in Fig, 1) by the action of a solenoid 30 illustrated as mounted upon the disk 28, and is projected by a spring 28. 1

As shown in Fig. 1, a source of illumination SL includes an electric lamp 32 and a lens system 33, with an enclosing housing to prevent escape of light except through a diaphragm 34. Mirrors 35, 36, 31 serve to deflect the light so that it passes through the balance wheel BW at a point betweenits hub and rim, whereby this light beam is interrupted each time a spoke of the balance whee] BW cuts across its path. The light beam from the source SL is thus guided and controlled, and enters the housing EL containing a photoelectric cell PE, and energizes this cell selectively in accordance with its own control by the action of the spokes of the balance wheel BW.

A shaft 40 is supported on the base 10 by a bearcall PE and the number increasing light, in

in: 4| and has'a crank 62 rocked. The shaft supports ing teeth engaged with the: supporting member 26 can angle by actuating the crank 42. An. electrical contact 66 is illustrated as carried by the sector arm 46 for selective engagement at the limits oi its rocking movement with contacts 66, 61, which are insulatediy mounted on the general fram it. The contacts 46, 61 are illustrated as adjustable screw elements so that their eflective positions can be changed for determining the end positions of the roclr shaft 66, and thus of the member 26.

The support l6 also receive a housing 66 to by which it lnaydm a sector rack 46 havbe .turned through an which air may be supplied under pressure through 62 with its orifice apipe6i,andwhichhasanomle adjacent the rim of the balance wheel ZBW. As shown in Fig. 3, this housing 66 has a slide valve l6i movable therein by a spring I 56 and by the armature I66 01 an electromagnetic coil ill connected to conductors H6 and H2. The valve l6l has the groove I62 which, upon energization of the coil III, is brought into alignment with the portsot the supply line'6i and the nozzle 62, so that a pull! of air is then blown through the nozzle uluier controlled conditio as described in my co-pending application, Serial No. 443,997, filed May 21, 1942.

As conventionally shown in the circuit diagram portions of Fig. la, the photoelectric cell PE is so connected that upon illumination thereof, current will flow through an amplifier 66 for supplying several control devices, .the connection of the of stages in the amplifier 66 being arranged to provide positive voltage with the illustrated fonn.

' For simplicity in the diagram, the cathodes of the various tubes are-conventionalized as having heaters adJacent thereto, and an expert in the art will understand that any appropriate means may be employed for exciting the cathodes.

The amplifier 66 is connected to the counting circuits and devices, which include a potentiometer 6i and two electron tube 65, 66 of the gasconduction or Thyratron type. The cathodes of the two tubes are connected by a resistor 61, and the cathode of tube 66 is connected through a resistor 68 to a conductor 66 which may be regarded as a ground or reference-potential conductor. The grid of the tube 65 is connected to the potentiometer 6i through a condenser 12, and to the conductor 66 through a grid return resistor 16. The tube 66 likewise has a resistor return circuit, and is connected through a condenser 12a with the potentiometer M. The tube 66 has its anode connected through appropriate dropping resistors 16a, 16b to a conductor 16 which leads to the positive terminal of a steady source A of plate current. The anode of tube 66 is connected by conductor 16 to a contact 2 of the starting relay SR, with a return from the corresponding relay switch blade I by conductor 11 and an appropriate resistor 16a to the resistor 16b. Condenser i6, 16 are connected between the anodes or the respective tubes 65, 66 and the reference-potential conductor 66, so that they are in efl'ect connected in series between the tube anodes, and also provide in association with the individually corresponding plate resistors 16a, 16a a pair 01' control devices for eilecting the alternate action or the tubes 66, 66 so that these tubes pinion 26 so that the while the tube 66 is conducting, as comp re with the flow therethrough while the tube 66" is;conducting, permits delivering current impulsesjat' different voltage levels as the tubes alternately ot resistor 66 the tube 8| H in its grid alternately load and fire for the successive imthe current flowthrough the tire. 1 From the cathode of tube 66, a conductor '66 with a series condenser 66a. and control resistor 66b therein leads to the grid of a third electron tube 6|, likewise effective for delivering the said impulse established from the alternate actionv oi the tubes 66, 66. as set out hereinafter; a branched grid retum'conductor including a resistance 62 and a biasing source 62a leads to the reference-potential conductor 66 for controlling the grid charge in this tube to hold the tube normally in nonconductive condition. The anode of tube 6| is connected through resistor 66 with the source A. The cathode of the tube 6i is connected through a resistor 66 to the reference-potential conductor 66 and thus to the negative side 01' the steady source A, to provide a positive impulse to the indicating device Q, when tube 6i conducts. A condenser 66 is connected between the negative end and the anode of the tube and, in association with the resistor 63, provides an RC network as a timing device for controlling the tube 6! which is quickly discharged upon receiving a sufiiciently high positive impulse but requires a predetermined time of recharging before it can again respond by discharging. This time is adjusted to be greater than the time elapslng between points b and 1 (Figs. 5 and 6), and will be described more in detail hereinafter. The source A maintains steady voltages on tubes 66, 66 and 6i, and the output voltage from tube 66 is very constant while it is passing current; and hence it will activate tube 6i only when the plate voltage of this tube has reached a certain value by this recharging of the RC network, and thus will be maintained inoperative until the normal time interval from b to f has been exceeded.

The time necessary for condenser 66 to recharge is determined by the value of condenser 66 (for example, 0.5 microfarad) and the series resistor 63 (for example, 400,000 ohms) with a selected supply voltage (for example, 300 volts). From the cathode of tube 6| leads an output conductor 66 which includes a series condenser 96:: and which may be .connected to any desired type of indicator Q, being illustratively conventionalized as an oscilloscope with associated timebase circuit. A return conductor 6| leads from the device Q to the reference-potential conductor 66.

The normal or does not vary through wide limits. For example, it the period varied plus or minus 72 minutes per day, this would only be a variation of 5 percent. The period can therefore be considered essentially constant within such limits. It is desired to maintain the motion swing of the balance at 1% turns which is approximately that utilized by the balance in a watch. Regardless 01' whether a balance swings 1% turns, 1 turn, or 2 turns (overbank condition), the overall time taken for a complete cycle is approximately the same within very close limits, whereas the change in amplitude of motion may vary 33 percent (1V: to 2 turns). Thus, in order to swing through the same time, the angular rate must increase. Conversely, de-

oi gas conduction type and is proper motion oi the balance a decreased angular style of rate. Since the light spot covers a fixed angle, preferably made equal to the spoke width for the wheel being tested, the time required to scan this spot is less for high amplitudes and greater for low amplitude The time required for any one impulse, due to the spoke intercepting the light, depends largely on the total swing of the balance, and in fact, when the wheel is at correct time, the impulse time varies inversely with the motion.

A safety device is the system will only provided for assuring that be made ready and released for operation when the balance wheel has been accurately set with a spoke lying in the neutral axis for intercepting the light which normally ialls on the photoelectric cell, and for operation of the machine if this condition is not met. This safety device also assures that the winding pin or plunger 21 will only move forward when the balance spoke is properly in position to prevent contact by the winding pin; and to prevent forward movement of the winding pin or plunger 21 while the. balance is oscillating.

For this purpose, the exciter lamp 32 is energized from an alternating current source, through preventin a transformer HI and a rectifier I40, with the 1 inclusion of an electrical filter circuit comprising the input choke coil I42, a further choke coil I43 and the smoothing condensers I44, along with a steadying bleeder resistor I45. This filter, however, is so constructed and designed that it permits a ripple of alternating current to pass to the exciter lamp of such an intensity that on the one hand the ripple has no effect upon the normal operation of the tubes 65, 66, but on the other hand is of. such value that upon further amplification and rectification it can provide a voltage for determining the operation of the winding solenoid 38.

A starter relay SR has and two contact blades. condition of normally closes a circuit between terminals I, 2 for the conductors 16, 11. The contact blade I23 normally closes a circuit between contacts 3, 4.

A control relay CR has an energizing coil I25 for moving the normally closed contact blade I28 and thereby opening a circuit between terminals 1, 8.

When the crank arm 42 is in the position shown in Fig. 1, contact 45 is engaged with contact 41 corresponding to the "vibrate" position. In this condition, current is taken by conductor I21 from a part of the steady source A and passes through coil I25 of the control relay CR, and thence to contact 41, through contact 45, and back through the conductor 69 to the source A: control relay CR is energized, and its contacts 1, 8 are open so that the coil I2I of the starter relay SR i deenergized, wherewith contacts 3, 4 are closed and the solenoid 38 is energized and holds the plunger 21 retracted. When the crank arm 42 is moved toward the opposite position, contact 45 leaves contact 41 and current no longer flows through coil I25, so that the relay OR is de-energized, and its contacts 1, 8 are closed and thus prepare the plate circuit of tube I55 by a path leading from the anode of tube I55 through coil I2I of relay SR by conductor I30, contacts I, 8 through the contact blade I26 of relay CR, with a return to conductor 15 and the steady source A, this steady source also being connected by conductor 68 and through resistances I51, I56 with the cathode of tube I55. It will be noted that the tube I55 is still held biased by resistors I51, I56, so that. no

the energizing coil I2I In the de-energized the coil I2I, the contact blade I22 current passes through this tube. Hence coll I2I continues de-energized, and current flows as betore through contacts 3, 4 and maintains energization of the solenoid 38, with retraction of the plunger 21. When the crank arm 42 has been moved until contact 45 engages contact 46 in the "wind position, the resistor I51 is short circuited, whereby the tube I55 may become conductive, provided that the voltage across resistor 252 does not impose a negative potential at the grid of tube I55 exceeding the firing potential of this tube; that is, 'a control can be exercised from tube I46 upon the tube I55 independently or the position of the crank arm 42. when conditions established through tube I48 and by the contact 45 concur, the tube I55 fires and current then flows through the anode path which has been tentatively established through contacts 1, 8 of relay CR, as set out above, and therewith the solenoid I2I oi the relay SR is energized, the contact blade I23 is attracted, and contact points 3, 4 are opened so that current can no longer flow through conductor I28 to the solenoid 38. Hence the solenoid 36 is de-energized and plunger 21 is released to move into its position (Fig. 2) under the action of spring 28, so that it can now engage the balance wheel spoke upon a further movement of crank arm 42.

The coil I2I of relay SR is connected by conductor ISO to terminal 1 oi the blade I28 of control relay CR; and terminal 8 of relay CR is connected to conductor 15, so that energizing current may flow from the source A to the coil I2I and thus supply anode current to the control tube system, when the control relay CR is deenergized.

The conductor is employed to control the amplifier tube I46 which has a diode section, this conductor 95 being connected to one end of a potentiometer I41 which is connected at its other terminal to the reference-potential conductor 69. The variable tap of the potentiometer I41 is connected to the grid of the tube I46. The cathode of this tube I46 is connected through a cathode resistor I48, with a by-pass condenser I49, to the conductor 69. The anode of the tube I46 is connected through a resistor 258 with the conductor 15 connected to the positive terminal of the steady source A. A condenser 25I is connected between the main anode and the diode anode of the tube I46, anda further connection is established from the diode anode through a resistor 252 to the conductor 69, and also through resistor 253 to the grid of the gas discharge tube I55. The grid of the tube I55 is connected through condenser 254 to conductor 68.

The gas discharge tube I55 has its cathode connected through the series resistors I56, I51 with the reference-potential conductor 69. The anode of the tube I55 is connected to the coil I2! of a starting relay SR. A resistor I59 is connected between the cathode of the tube I55 and the positive conductor 15. The conductor I3I from the "wind" contact 46 is connected to the common central connection of the resistors I58, I51, so that resistor I51 is short-circuited when the lever is in the wind position.

Thus, while the balance wheel is being mount-' ed, if light passes from the exciter lamp 32 to the photoelectric cell PE, this cell is energized,

and the ripple effect appears across the potentiometer I41 and the tube I46 delivers a negative accuracy and amplitude the resistors I56, I51 in the cathode circuit. The resistor I5! is connected in series with resistors I56, I 51, and causes current to fiow therethrough and thus sets up sufilcient voltage to keep the tube I55 in a normally non-conductive state, since the cathode of this tube is at a relatively positive potential with respect to conductor 65, and the grid is maintained negative by the amount determined by the current fiow through resistors I59, I56, I51. The resistors I56, I51 are so proportioned that when resistor I51 is short-circuited, the bias established by resistor I56 will be Just sufiicient to permit the tube I55 to fire. This short-circuiting is accomplished by moving the control crank 42 into the wind" position.

When light falls upon the photoelectric cell PE, the negative voltage at the diode of tube I46 is impressed upon the grid of tube I55, and can maintain this tube against firing, even if resistor I51 is short-circuited. When the spoke of the balance wheel BW is in the neutral axis, however, the light is cut oil from the photoelectric cell PE, and the delivery of negative voltage from the diode of tube I46 ceases, so that the tube I55 is permitted to fire, thus delivering current for activating energizing coil I2I of the relay SR.

The resistors 252, 253 also provide with the condenser 254 an RC filter for smoothing out voltage fluctuations which appear across the rectifier, and operates as a timing circuit for determining the rate of drop of the negative voltage derived from the diode of tube I46. Thus, if the oscillating as a result of prelimmary mechanical adjustment, the drop of the negative voltage across the condenser 254 is so slow that the grid of tube I55 is not aiforded opportumty to permit firing of this tube prior to counters the photoelectric cell PE. Hence, the spoke must be essentially quiescent and at the neutral axis before the tube I55 can fire.

Before describing the operation of the parts, it may be pointed out that the path of the light beam LB (Figs. 1 and 4) is fixed, and it is preferable so to adjust the condenser lenses and diaphragm structures 33, 34 that the transverse dimension of this beam corresponds to the width of the spokes of the balance wheel BW at the point of interception, as this gives an optimum of response. Each time shadowed. Thus, if the balance wheel BW, which is illustrated as having the usual two diametrically opposed spokes, is rocked through an arc of less than 180 degrees in each direction from a neutral axis NA (Fig. 4), only the lower spoke intercepts the beam, and there is one obscuring efiect at each stroke, or two for a complete cycle of movement for the balance wheel BW. If the balance wheel is rocking in each direction through an are greater than 180 degrees and less than 360 degrees, then both'spokes intercept the In current practice with watch escapements,

. 2,856,078 remains in the non-conductive state because 0! the balance swings through an are greater than degrees and less than 860 degrees in each direction from the neutral; axis. Since the rate of the oscillatory system may vary slightly when the balance swings through angles less than those employed in actual practice, it is desirable to determine the rate at substantially the same amplitude of oscillation as is performed by the balance while in service.

The successive interceptions may be represented diagrammatically as in Fig. 5, where a curve I60 represents the rocking movement of the balance wheel BW and is conventionally shown as sinusoidal, although it will be understood that departures from strict sinusoidal condition are not unusual, usually by change of the slopes representing the forward or tick" stroke or the rearward or "took" stroke relative to one another. For accurate maintenance of time by the balance wheel, it is only necessary that thetime interval from cycle to cycle between successive moments at which the balance wheel operates to release the train in a "tick" movement or in a tock" movement shall be constant, and the time spacing from the "tick" release to the took release need not be the same as that from the toe release to the "tick" release. preferred construction is to have the balance release; .thetiming train at the moment of maximum'velocity of the balance, this release normally occurs both for the "tick and the tock" movements substantially at the neutral axis NA.

If the movement of the balance wheel BW is followed along the curve I60 of Fig. 5, beginning with the balance wheel at a point I6I at which it has been displaced from the neutral axis NA through an angle greater than 270 degrees but less A spoke after the winding through 330 degrees for example) crosses the light beam LB during this acceleration at a point 180 degrees from the neutral axis and causes a first electric impulse a. The balance wheel continues its acceleration under the urgency of the hair spring and at the neutral axis, a second impulse b of much shorter duration is produced by the interception of the other spoke (the lower in Fig. 4). during this "tick" stroke, the balance wheel BW slows down or decelerates as it is now engaged in winding the hair spring, so that when the upper spoke (of Fig. 4) next passes the light beam LB, a longer impulse c is again produced at 180 degrees from the neutral axis. Ultimately, the balance wheel BW comes to a standstill at a maximum amplitude around 330 degrees, and then returns in the tool-r" stroke. In a watch or like movement, the pressure from the timing train adds to the energy of the balance wheel system so that the frictional and other losses are substantially compensated during each cycle and stroke. In the present device, energy is supplied from the maintaining device 50 for a like purpose.

After leaving the point I62 plitude at the end of the "tick" stroke, the balance wheel BW begins to move backward under the urgency of the power stored in the hair spring, and during the course of its acceleration, the upper spoke again intercepts the light beam LB at substantially 180 degrees from the neutral axis to give an impulse d of relatively long duration; and then, as the balance wheel continues to accelerate, the lower spoke intercepts the light of maximum am- Since a.

Thereafter,

velocity to provide a short impulse e. As before,-

the balance wheel BW now decelerates, and a final long impulse I in the took stroke is given by the upper spoke at 180 degrees after the neutral axis; finally the balance wheel BW comes to a standstill at a maximum amplitude of movement represented by the point I63 at the end of the took stroke; and a tick" stroke begins the next cycle. These "tick" and "took strokes alternate, and each pair constitutes a cycle of movement of the balance.

It may further be pointed out that the dottedline curve I64 in Fig. represents a movement of the balance wheel BW which is in synchronism with the movement represented by the curve I60, but in which the balance wheel is moving through a smaller amplitude or lesser angles (being only slightly greater than 180 degrees). The slopes of the flanks of the curve I64 are much lower than those of the curve I66, and the upper spoke which intercepts the light beam LB at 180 degrees from the neutral axis is moving much more slowly than described above, so that the impulses f and a are much longer than the corresponding impulses j and a. for the curve I60. Furthermore, in Fig. 6, the impulses a, b, c are indicated in their time relationship to one another corresponding to the curve I66, and it will be noted that these individual impulses have short durations corresponding to definite basic frequencies. The triplet groups of impulses are substantially spaced apart because a large part of the total time in each cycle is consumed in slowing down, reversing and returning during the part the angular movement which ismore than 180 degrees from the neutral axis, in either direction. However, when the amplitude of movement decreases, a lesser proportion of the time is consumed in these portions of the cycle, so that the successive impulses (Fig. 7) with the curve I64 are individually of greater time duration, and they are farther apart within the triplets, and the end members 0, d and ,f, a of adjacent triplets are much closer together: in particular, with an amplitude of 180 degrees, the impulses will coincide.

In operation, the crank handle 42 is initially in the vibrate position, (as shown in Fig. l) i. e. with contact 45 engaged with contact 41. Power is supplied to the electrical circuits and to the lamp 32, and compressed air to the pipe 5|. The knob I9 is withdrawn and a balance is inserted into the support 23, and then the knob I9 is released again, so that the balance is now supported for free rocking movement upon the members I6. 23. It will be noted that this is accomplished without any particular orientation of the balance. The hair spring HS is then clamped in the pincers I5 at a point of its length which is believed to represent the proper length of hair spring for accurate timing, the balance rotating about its axis as necessary for this adjustment.

The disk I3 is then turned about its axis until one spoke of the balance wheel (the lower spoke in the illustrative form. Fig. 4) intercepts the li ht beam LB while the balance wheel BW is at rest; t is operation establishes the balance at the predetermined neutral axis NA (Figs. 4 and 5). During these adjustments. the balance is turned slowly. and soon comes to rest in the desired initial position.

With the crank handle 42 and the sector 43 in the vibrate position for the insertion and orien.. tation of the balance wheel. the contact 45 engages the contact 41; the control relay CR is energized and current also flows between terminals 3, 4 or the starter relay SR for energizing the winding solenoid 30 so that the plunger pin 21 is held in its right-hand or retracted position in Figs. 1 and 2, and does not interfere with the manipulations of inserting and orienting the balance wheel. Current also can flow between terminals I, 2 of the starter relay SR, so that the anode circuit of tube 65 is closed. The operator now shifts the crank 42 in a clockwise direction (Fig. 1) from the "vibrate" toward the "wind position, so that the sector rack 43 drives pinion 25 and turns the 'disk 26 counter-clockwise through an angle established by the spacing of the contacts 46, 41 in this illustrative form. The plunger or winding pin 21 is held retracted, so that the disk 26 turns independently or the balance wheel BW, the latter remaining essentially without movement. This disk 28 and the winding pin 21 are turned (counter-clockwise or in the direction oi the arrow in Fig. 3) through an angle between 360 and 450 degrees. By the original location of the winding pin 2'! relative to the spokes of the balance wheel BW, this preferably results in bringing the winding pin TI to rest, when the contact 45 engages the contact 46 in the wind position with the winding pin 27 in an angular position midway between the spokes or at degrees to the neutral axis, so that the pin 2! can move outward or toward the left in Fig. 2 without encountering a spoke of the balance wheel BW. When the contact 45 engages contact 46, further movement of the disk 26 is prevented. and also an electrical circuit is set up through the short-circuitin of resistance I51 so that the tube I55 passes current and energizes the coil I2| of the relay SR.

Energization of the relay SR causes the system to establish the conditions necessary for initiation of the testing operation. Opening of contacts 3, 4 causes de-energization of the winding solenoid 30 so that the winding pin 21 moves outward or toward the left in Fig. 2. Contacts I, 2 of relay SR are opened so that the tube 65 ceases to receive any plate current and hence tube 66 is caused to fire and to continue to pass current.

The operator now shifts the crank 42 backward in a counter-clockwise direction (Fig. 1) from the "wind" to the vibrate" position, so that the sector rack 43 drives the pinion 25 and the disk 26 is turned clockwise through the aforesaid angle as established by the spacing of the contacts 46, 41. *When the contact 45 leaves the contact 46, the resistor I5'I is no longer short-circuited, but the tube I55 continues to pass current and to hold the coil I2I of relay SR energized, thus preventing false operation in the event of multiple partial movements of the crank 42 or in the event of chatter at the contacts 45, 46. The winding pin 21 during the mechanical movement ultimately engages a spoke of the balance wheel BWand turns the balance in aclockwise direction (Fig. 1) so that this balance is displaced against torsion of the hair spring through an angle in excess of 270 degrees, this angle preferably being adjusted to be about 330 degrees, but insufflcient to cause a spoke to twice pass the beam of light. Thus, it is normally preferred to have the winding pin 2'! move through 90 degrees (less the radius of the pin 21 and one-half the width of the spoke) before it encounters a spoke of the balance, and then move through a further distance amounting to the aforesaid angle of 270 to 330 degrees or more,.before the lever 42 of the relay SR is lie-energized. This de-energization of relay SR leads to the starting of the mechanical and electrical operations of timing.

Contacts I, 2 reestablish a plate circuit for the tube 65, and contacts 3, I close to re-energize the coil of the solenoid 30 so that the winding pin 81 is retracted toward the right in Fig. 2.

. With the retraction of the winding pin 21, the balance begins to turn in response to the torsion exerted by the hair spring, and assumes an oscillatory motion as indicated in Fig. 5, so that its spokes successively interrupt the light beam.

When the balance wheel BW is released, it performs its oscillatory movement, and produces the successive impulses a, b, c, d, e, f during each cycle, as stated hereinbefore. ,The tube 66 is conducting, and the first or a impulse causes the tube 65 to fire and the tube 66 to be extinguished. The tube 8| has a high voltage differential between its cathode and anode owing to the charge in condenser 89, but is prevented from firing owing to the negative charge on its grid which is not overcome by the relatively low current impulse from the tube 65, because the current flow through this tube 65 also passes through both resistors 61, 68.

The second or b impulse causes the tube 66 to fire and the tube 65 to be extinguished. The firing of tube 66 causes a greater current to fiow through the single or common cathode resistor 68, and hence a relatively more positive potential to be placed on the grid of the tube 8|, and this tube in turn will fire so that a current-impulse flows by conductor 80 to the indicator Q. The condenser 88 discharges through the tube 8| and the cathode resistor 86 until its charge potential drops to a point below the critical voltage of the tube 8|, the dropping occurring at a rapid rate due to the relatively low resistance of the tube 8| conducting. Current fiow through the tube 8| then ceases, and the cathode end 01' the conductor 88 returns to the initial potential.

The third or c impulse causes the tube 65 to me and the tube 66 to be extinguished. The relatively positive potential at the grid of the tube 8| ceases, and tube 8| can now become nonconductive as the charge of condenser 89 is dissipated. Condenser 89 begins to recharge from the source A at a rate determined by the resistor 88. The balance wheel now attains the end 01' its forward or "tick" stroke, and reverses.

The fourth or d impulse causes the tube 66 tofire and the tube 65 to be extinguished. The potential across the condenser 89 has not built up to a point where it can pass through the tube 6| at the grid potential produced upon the firing oi' the tube 66.

The fifth or e impulse causes the tube 65 to fire and the tube 66 to be extinguished.

The sixth or 1 impulse causes the tube 66 to fire and the tube 65 to be extinguished. The condenser 89 has not yet received a sufiicient charge for discharge through the tube 8| under the grid condition now prevailing'at that tube.

The balance wheel now attains the end of its rearward stroke, and reverses to start a new cycle,

At the first or a impulse of the new cycle, the tube 65 is fired while tial at the grid of the tube now fires again owing to the The condenser 89 is now attaining a charged condition. a

At the second or b impulse of the new cycle, the tube 66 is fired, and the tube 65 extinguished. The tube 66 acts to deliver current which establishes once more a relatively more positive poten- 8|, and this tube 8| combination of proper anode-cathode and grid-cathode voltages, and a further impulse passes to the indicator Q.

The sequences continue so long as the system is in the determining condition.

Thus, only at the b impulse out bf each cycle of six impulses is the tube 8| caused to fire; and the assembly is selective of the impulses of the b type, which are produced at the moment when the balance passes its neutral axls,being thus moving at its maximum velocity in a forward" direction or on the tick stroke in this illustrative example.

The alternate firing action of tubes 66 and '65 is a result 01' varying voltages obtained during transient conditions.

-By the term "gasconduction tube is meant herein an electron discharge tube usually having a gaseous content and by which a relatively negative voltage upon a grid will inhibit the effective passage of current at a, predetermined voltage between cathode and anode, while the presence of a predetermined relatively more positive potential upon the grid will provoke the passage of current from cathode and anode, i. e., the firing of the tube; with a further characteristic that the established flow of current at such voltage between cathode and anodewill continue substantially free from control by changes of grid potential, until the voltage between the cathode and anode has been so reduced below a certain critical value that the grid can again take charge and and the tube 66 extinguished. (5

stop the fiow. This action is obtained for example in the circuit shown for tubes 65 and 66 by distributing the voltages across the condensers, resistors and tubes so that the transients appearing across the common cathode resistor 68 provides the desired effect.

With tube 66 conducting, and the source A maintaining 300 volts between conductors 69, 15, voltages during the steady state are so distributed that, for example, 45 volts appears across resistor 68, 15 across tube .66, and volts across condenser 19 since this condenser is in parallel to the tube 66 and resistor 68. 92 volts appears across the anode resistor 19a, and 148 volts across the common anode resistor 19b. Condenser 18 charges up to 152 volts, as the entire 300 volts is applied to this condenser 18 except for the drop across resistor 19b. Not all of this appears across tube 65, however, as 45 volts appears on the cathode resistor 68 to reduce the voltage on tube by that 'amount. The tube 65 remains nonconducting due to the biasing effect of resistor 68 until an impulse of sufilcient amplitude from the input drives its grid positive. When this occurs, the tube 65 fires and passes current, and a transient condition obtains so that the minimum voltage for conduction in tube 66 is no longer present, and hence tube 66 becomes nonconducting and is extinguished. This is accomplished by maintaining constant the plate voltage supply to a conducting tube and its associated circuit elements, and increasing the voltage between the tube cathode and the reference-potential conductor 69, so that the effective voltage across the tube is lowered below that necessary for conduction.

aasao're During the preceding steady state, condenser 18 has been charged to 152 volts, and the remainder of 148 volts has appeared across tube 65. At the instant tube 65 begins to conduct, the current through resistor 68 increases above .004 amp. due to the condenser 18 discharging through tube 65, resistor 61 and resistor'88. The cathodes of both tubes 65, 66 are then raised in voltage in a positive direction. The anode of tube 66 cannot rise instantaneously in relative potential, however, due to the stabilizing effect of condenser 19, as a condenser cannot charge instantaneously. Thus momentarily the tube voltage is reduced sufilciently. to cause it to extinguish and become nonconductive. The extinguishing action is further assisted by a voltage drop appearing across resistor 19b due to the current surge through tube 65, part of which comes from resistors 18a and 19b. It can be seen that if tubes 66, and 65 were conductive at the same time, approximately twice the normal current wouldfiow through resistor 18b, thus causing a very large voltage drop thereon. Tube 66 is maintained non-conducting until steady conditions are again reached as thedischarge of condenser 18 causes increased voltage to appear across resistor 68, which biases the tube since it is between the cathode and the referencepotential conductor 69.

The actions of tubes 66 and 65 are identical in that as each tube is caused to fire, the other tube is extinguished; the resistor 61 is included in the cathode circuit of tube 66 in order to reduce the transient voltage caused across resistor 68 while tube 65 is conducting. In this illustrative employment, the transients provided by tube 65 and appearing between the terminal of conductor an and the reference-potential conductor 69 are used to activate the further tube 8|. Resistor 61 reduced the transient current flowing through tube 65, thus reducing the transient voltage on resistor 58 caused by that tube.

It will be noted that the indicator Q performs its action when the tube 8| fires, which represents a succession of impulses to the indicator Q at the course of the impulses b for the successive cycles, representing the maximum velocity of movement of the balance during the tick" stroke of each cycle.

When the indicator Q is a cathode ray tube, the time base circuit may be adjusted to the standard frequency. Then the successive impulses from the tube 8| will appear as visible deflections or "traces" of the cathode beam at an acute angle to the line established by the time-base oscillation effect. I If the watch movement under test is not moving at the standard rate, these deflections will occur at successively different parts of the time-base cycle, and will have the appearance of drifting" at a rate representing the amount of departure from the standard rate. The direction and amount of drift may be noted, and constitutes information by which the movement may be adjusted into coincidence with the standard rate.

When this determination has been made, the operator terminates the determination by moving the crank 42 in a clockwise direction (Fig. 1) from the vibrate position. Contact 45 is separated from contact 41, and relay CR is deenergized. Contacts 1, 8 are permitted to close, so that as permitted by the safety control, the currents in conductor 95 can again cause tubes Contacts I, 2 open the plate circuit of the tube 85, so that the alternate loading and firing of tubes 65 and 66 ceases. Contacts 3, 4 open the circuit through the winding solenoid 30 so that the pin 21 can move outward under the safety control into position between the spokes of the balance wheel.

The balance BW can now be removed. The crank 42 may be moved back to the "vibrate position before or after the balance is removed: as the balance is at a standstill, this has no effect in causing movement of the balance. A new balance can be inserted as before, and the sequence of mechanical movement of the crank 42 conditions the system for a further testing operation.

Observation of the record at the indicator Q permits the operator to determine whether the balance is at the desired timing or not.

In the circuits shown in the figures, it will be noted that the resistors and condensers are shown conventionally at proper points for show- I46, I55 to conduct current, and current through ing the entire action-of the electron discharge tubes and for preventing the imposition of improper direct or straight current impulses by which improper energizations might be obtained as shown by experts in the art. The proper sizes and electrical values of these in constructional employment form no part of the invention save and except as they constitute parts of the illustrative circuits for attaining the purposes stated.

It is obvious that the invention is not limited to the illustrated form or purpose, but may be employed in many ways within the scope of the appended claims.

I claim:

- 1. An apparatus for employment during rating of balance assemblies and like devices including springs, comprising 'a, frame, a first member mounted to move axially and to rock on said frame and constructed to support one end of the device when the member is in one axially-moved position, means to hold the member in its supporting position, a second member movable about the axis of said first member and having means for supporting the other end of the device, gripper means carried by one of said members for engaging the spring of the device, said one member being movable about said axis to permit positioning movement of the device about its own axis. and a movable detent carried eccentrically by the other of said members for selective engagement with said device for moving the same into a stressed condition and for releasing the same for oscillation.

2. An apparatus for employment during rating of balance assemblies and like devices including springs, comprising a frame, means on the frame for supporting one end of the device, a member siidable on the frame and having an apertured end for receiving the other end of the device to support the same in position for oscillation, spring means for sliding the member into its holding position, gripper means carried by the frame and movable about the axis of said device for engagement with the spring of the device and effective for moving the device into a desired neutral static position, a pin movable substantially parallel to said axis between positions in which it is in the path of movement of the device and in which it is out of said path, and means on the frame to move said pin in a path about said. axis whereby to place the device in a stressed condition.

3. An apparatus for rating balance assemblies positioning the device at a tioning the device at a static position, a

and like oscillatory devices including springs; comprising a frame, two spaced members on the frame separately {rotatable about a common axis and including means for supporting the device, one of said members having means for engaging the spring and eflective upon rotation to position the device at a predetermined neutral static position, the other said member having a retractable detent carried thereby for engagement in one position with device for storing energy in the spring when the said other member is rotated, and means for controlling the position of the detent and effective for retracting the detent from said one position thereof after a predetermined amount of energy-storing movement of said other member.

4. An apparatus for rating balance assemblies and like oscillatory devices including springs, comprising a frame, two spaced members on the frame separately rotatable about a common axis and including means for supporting the device, one of said members having means for engaging the spring and eifective upon rotation to position the device at a predetermined neutral static position, the other said member having a retractable detent eccentrically carried thereby and movable in a direction substantially parallel to the common axis for engagement in one position with the device for storing energy in the spring when the said other member is rotated, means for determining and indicating the rate of said device, and means for controlling said determining and indicating means and for controlling the position of said detent and eflective for simultaneously retracting the detent from said one position thereof and for starting the determination of the rate of the device.

5. An apparatus for employment during rating of balance assemblies and like devices including springs, comprising a frame, means on the frame for supporting the device for free oscillation about its axis, means for engaging the spring of the device at a .point oflset from the axis thereof and movable about said axis for-' predetermined neutral static position, a plunger pin for engaging within an aperture of the device, means for retracting and projecting said plunger pin, and means for translating the plunger pin about the axis of the device for storing energy within the spring.

6. An apparatus for employment during rating of balance assemblies and like devices including springs, comprising a frame, means on the frame for supporting the device for free oscillation about its axis, means for engaging the spring of the device at a point oflset from the axis thereof and movable about said, axis for posipredetermined neutral plunger pin for engaging withan aperture of the device, means for retracting and projecting said plunger pin, and means for translating the plunger pin about the axis of the device for storing energy within the spring, said means including a pinion coaxial with the device, said plunger pin being supported to be translated with said pinion by a common angular movement, a toothed member for rotating said pinion and effective for moving it through an angle of more than 270 degrees, and limit stops for determining the stroke of said toothed member.

7. A rating apparatus for periodically oscillating devices comprising a support upon which the device is placed for oscillation, a retractable detent for selectively engaging said device, means for moving said detent along the path of oscillation for storing energy in said device, a source of light and means for producing a fluctuating beam of light from said source, said device including a portion for interrupting said beam of light when the device is in a predetermined initial static position, a photo-sensitive member in the path of said beam and responsive to the fluctuations and interruptions thereof, and means connected to said member for controlling said detent so that the same can only be positioned for engagement with said device when the device has been initially statically positioned in said predetermined position. I

8. A rating apparatus for watch and like balances, comprising a support upon which the device is placed for oscillation, a retractable detent for selectively engaging said balance, a rocker formoving said detent along the path of oscillation whereby to store energy in said balance, means for scanning the balance and effective for determining when a selected part of the balance is located at a neutral static position, and means responsive to said scanning and determining means for controlling the detent for preventing cooperative engagement of the detent and balance except when the balance has been initially statically positioned at the said neutral position.

9. A rating apparatus for periodically oscillating devices, comprising a support upon which the device is placed for oscillation, means for storing energy in the device whereby it may perform oscillations and including a rocker and a retractable detent carried by the rocker, contacts selectively engaged when the rocker is brought into its end limit positions, a first relay energized through said contacts when the rocker is in one limit position, a second relay, means responsive to the transitsof the device in its oscillation for energizing said second relay and including means controlled by said contacts for determining the cessation of energizationof the second relay when the rocker is in the other limit position, said first relay including contacts which are normally closed for establishing an energizing path for said second relay, and circuit means controlled by aid second relay for determining the position of said detent so that the detent is advanced into engaging position when the device is initially placed at the neutral axis and is retracted therefrom when the device has been moved to a predetermined energy-stored position.

10. A rating apparatus for periodically oscillating devices, comprising means for supporting the device for oscillating movement, means for scanning the movement of the device, said device including elements which pulses in the scanning means at predetermined distances ,of angular movements of the device,- said scanning means including a part positioned and arranged so that one of said impulses during each cycle is produced at the time when the device is moving at substantially its maximum velocity, means responsive to said impulses and eirective for selecting said one impulse during each cycle of oscillation, and an indicator for showing the time relationship between the successive selected impulses,

11. A rating apparatus for watch and like balances, comprising a holder in which the balance may oscillate about its axis, a member rotatable produce periodic imabout said axis, a detent carried for translation by saidmember and movable into and retractable from the path of the oscillating movement, means for moving said member whereby the detent when in one position can engage and move the balance, and means responsive to the movement of said moving means for controlling the position of said detent whereby to retract the detent from engagement with said balance after a predetermined movement of said member.

12. A rating apparatus for watch and like balances, comprising a holder in which the balance may oscillate about its axis, a member rotatable about said axis, a detent carried for translation by said member and movable into and retractable from the path of the oscillating movement, means for rocking said member through an angle greater than 270 degrees, contacts closable by said rocking means at its limits of movement, and circuit means controlled by said contacts for determining the position of said detent whereby to retract the detent from engagement with said balance after a predetermined movement of said member.

13. A timing apparatus for hair spring balances including supporting means for the balance, means including a clamping device for the hair spring and effective for initially positioning the balance at a predetermined neutral static position, means for determining the oscillatory movement of the balance, and a rockable member for moving said balance through a predetermined initial angle about its axis, and having thereon a retractable detent carried eccentrically on said member and movable toward and from the balance and efieotive in one position for engaging said balance, and devices connected with said detent for releasing the balance at the end of a predetermined rocking movement and also efiective for energizing said movement determining means.

14. An apparatus for determining the timing of a device having a diametrically extending element of limited width which oscillates periodically through an are greater than 180 degrees and less than 360 degrees, which comprises means responsive to selected positions of oscillation of said element for generating a group of impulses at each stroke of said element, one of said impulses being generated at the moment of substantially maximum angular velocity of the element and others at intervals therefrom representing substantially 180 degrees of angular movement before and after said one impulse, and discriminating and indicating means selectively responsive to the impulses for showing the time relationship between the said one impulses of each alternate group.

15. An apparatus for determining the timing of a device having a diametrically extending element of limited width which oscillates periodically through an are greater than 180 degrees and less than 360 degrees, which comprises photoelectric means for scanning the oscillatory movement of said element essentially opposite the point at which the element attains its maximum angular velocity, said scanning means being effective at each stroke of said element for generating a group of electrical impulses, one of said impulses of each group being generated at the moment of substantially maximum angular velocity of the element and others at intervals therefrom representing substantially 180 degrees of angular movement before and after said one impulse, discriminating and indicating means selectively responsive to the impulses for showing the time relationship between the said one impulses of each alternate group.

16. An apparatus for determining the time of harmonically oscillating elements having lightobscuring portions of limited width, comprising photo-electric means for scanning the element during its oscillatory movement and establishing a primary impulse when an obscuring portion has substantially its maximum angular velocity, said element oscillating during each stroke through such an are that secondary impulses are established by said scanning means before and after said primary impulse, and discriminating and indicating means selectively actuated by the impulses for determining the time intervals between said primary impulses.

17. An apparatus for determining the timing of harmonically oscillating elements having lightobscuring portions, comprising means for supporting said element, photo-electric means for scanning the said element during oscillatory movement and for establishing electrical impulses at the passage of said light-obscuring portions, the impulses established during each stroke constituting a group, a rockable device for engaging and initially moving said element through a predetermined arc and including means for releasing said device from the element whereby the latter is freed to perform oscillatory movements, discriminating means for selectively responding to the electrical impulses, and indicating means responsive to said discriminating means for showing a selected impulse in each alternate group, and means controlled coordinately with said releasing means for initiating the action of said discriminating means concurrently with the initiation of movement of said element.

18. An apparatus for rating balance assemblies and like oscillatory devices including springs, comprising a frame, means for positioning the device for oscillatory movement and including gripper means for engaging the spring thereof, means for scanning the oscillatory movement of the device and generating thereby a group of electrical impulses for each cycle of the movement, one of said impulses being generated substantially at a point of maximum velocity of movement of the element in one direction and others at intervals of angular movement therefrom, means for discriminating between the impulses'of each cycle of movement, and indicating means controlled by the discriminating means and effective for successionally indicating the said one impulse of each cycle.

19. An apparatus for rating balance assemblies and-like oscillatory devices including spokes and springs, comprising a frame, two spaced members on the frame separately rotatable about a common axis and including means to support the device, one of said members having means for engaging the spring and effective upon rotation to position the device at a predetermined neutral static position, the other said member having an eccentrically located plunger, said plunger in one position lying in the path of oscillatory movement of a spoke and in another position being withdrawn therefrom, means for rocking said other member whereby to wind the device through a predetermined angle to store energy in the spring, and means for retracting said plunger after completion of the winding movement.

20. An apparatus for determining the timing of a device having a plurality of angularly-spaced ing a part so positioned and arranged that dur--.

ing each cycle one of said impulses is generated substantially at the moment of the maximum angular velocity of the device in one direction and other impulses at intervals from said one impulse representing angular movements corresponding to the angular spacing between the elements, and discriminating and indicating means selectively responsive to the impulses for showing the time relationship between said one impulses of each cycle.

21. An apparatus for determining the timing of a device having a plurality of angularly-spaced radially-extending elements of limited arcuate dimensions and which device oscillates periodically through an are greater thanthe angular spacing of successive radially-extending elements, which comprises means responsive to the passage of said elements during the oscillation of the device for generating a group of impulses at each stroke of said device,'said means including a part so positioned and arranged that during each stroke one 01' said impulses is generated substantially at the moment or the maximum angular velocity of the device and others at intervals from said one impulse representing angular movements corresponding to the angular spacing between the elements, and discriminating and indicating means selectively responsive to the impulses for showing the time intervals between said one impulses.

22. An apparatus for determining the timing of a structure having a diametrically extending element or a limited width which oscillates pe-- riodically through an are greater than 180 degrees and less than 380 degrees in each direction and attains substantially its maximum velocity. at its transits past a neutral axis. comprising means for scanning the oscillatory movement of the element and thereby generating a group of electrical impulses for each cycle of movement. each cyclic group comprising an impulse in each stroke of the cycle corresponding to the transit or said element past the neutral axis while moving at substantially maximum velocity and also comprising impulses corresponding to the transits of said element past the neutral axis during the accelerating and decelerating parts 01' each stroke of the cycle, means for discriminating between impulses of each group and effective for indicating the time intervals between selected maximum-velocity impulses of the successive groups.

23. A rating apparatus for hair spring balance and like oscillatory devices including a radially extending spoke, comprising a frame, means on the frame for supporting the device for oscillation, means for projecting a light beam across the path of oscillatory movement of the spoke,

said beam having a dimension in the direction oi said oscillatory path not essentially greater than the width of the spoke whereby the spoke can interrupt the beam, said supporting means including means for shifting the device along said path until said spoke lies in a predetermined neutral static position and across the light beam, means for winding and releasing the balancei'or setting the same in oscillation and including a member movable parallel to the balance axis into and out of a position for engaging the spoke, means responsive to the passage and the interruption of the light beam for indicating the rating or said device while oscillating on said supporting means, and means controlled by the said responsive means for preventing axial movement of said member into engaging position when the said member is opposite the spoke.

WALTER KOHLI-IAGEN. 

